The present invention relates to a distributed control system for semiconductor manufacturing equipment, and more particularly to a computer controlled apparatus and method for improving semiconductor processing.
In the semiconductor industry, various processes can be used to deposit and etch materials on the workpieces, which may also be referred to as wafers. These processes are typically carried out by various machine tools, or may be carried out in the same tool using various chambers. Conventional processing chambers are designed in multiple processing stations or modules that are arranged in a cluster to form a cluster tool or system. Such cluster tools or systems are often used to process a multiple number of wafers at the same time. Generally, cluster tools are configured with multiple processing stations or modules and are designed for a specific operation. However in such conventional cluster tools, deposition and cleaning processing steps both typically require separate chambers. Consequently, a wafer is typically moved to another station or system in order to be processed and cleaned. Since the environment must be clean of contaminants, a robot is typically used to move the workpiece from one chamber to another inside the cluster tool.
A software control program is used to control the robot for moving the workpieces around in the tool (called a production route), and for loading recipes to each of the processing chambers. The software control program is typically loaded by an operator selecting from a number of available production routes and recipes through a user interface. The operator loads a particular process recipe that includes information such as the chambers that will be used to process the semiconductor wafer, the parameters for processing, and other information.
Maintenance and testing of the chambers is a major business issue since an improperly operating chamber may cause downtime, resulting in lost production revenues. Conventional machine tools require that the cluster tool be taken offline for maintenance and testing. Consequently, a difficulty that arises in conventional equipment is that the individual chambers cannot necessarily be manually controlled while the equipment is in operation (i.e. the production route in running).
What is needed is a system that allows unused chambers to be manually controlled, tested and maintained while the equipment is in operation.
The present invention relates to a distributed control system for semiconductor manufacturing equipment, and more particularly to a computer controlled apparatus and method for improving semiconductor processing. The invention advantageously allows unused chambers to be manually controlled, tested and maintained while the equipment is in operation.
A semiconductor workpiece processing tool according to an embodiment of the invention includes a plurality of process modules for processing the workpiece, where a number of the process modules include a robot loading window and a manual loading window. A control system is provided for managing operation of the processing tool including a production route defining movement of the workpiece among a number of the process modules. The control system includes a user interface through which an operator can define the production route and recipes to be performed on the workpiece in each of the process modules, a system controller for controlling execution of the production route, a process module controller associated with each of the process modules for controlling the processing of the workpiece in the process module, and a network connecting the user interface, system controller and each process module controller. The system controller provides each process module controller with the recipe name, which is retrieved over the network The production route includes a number of online process modules defined in the production route. In the exemplary embodiment, at least one offline process module not included in the production route, and an offline process module can accept a workpiece through the manual window and to perform a recipe thereon.
In one aspect of the invention, the user interface is a graphical user interface. In another aspect of the invention, each process module controller is capable of retrieving the recipe over the network based on the recipe name. In yet another aspect of the invention, the offline module may be configured to perform testing, maintenance or other operation while the production route is in operation.
Advantages of the invention include the ability to continue a production route while manually operating a process module. As a result, the tool may continue in operation while selected process module are tested, maintained or otherwise used to process workpieces. This feature of continued operation while certain process modules undergo maintenance and testing can result in significant productivity improvements since the production line does not need to stop when a process module is undergoing maintenance and testing.